Magnetic head slider assembly for magnetic disk recording/reproducing apparatus

ABSTRACT

A magnetic head slider assembly for a magnetic disk type recording/reproducing apparatus includes a slider body, a sliding pad provided on the slider body and projecting beyond a disk facing surface thereof, a thin film layer disposed at one end of the slider body, a magnetic head constituted by the thin film layer as an integral part thereof, and a core pad projection incorporating therein a core of the magnetic head and projecting beyond an adjacent disk facing surface of the slider body. The sliding pad is provided at a region of the slider body ahead of the core pad projection and prevents generation of a floating force by making use of a relative movement between the slider body and the magnetic disk. The core pad projection is not formed as a continuation of the slider body and is separated from the sliding pad a predetermined distance longitudinally of the slider body by a recess interposed therebetween whereby the core pad projection is positioned closer to the magnetic disk than a back end of the sliding pad.

This is a continuation application of U.S. Ser. No. 08/529,803, filedSep. 18, 1995, now U.S. Pat. No. 5,886,856.

BACKGROUND OF THE INVENTION

The present invention relates generally to a magnetic head sliderassembly for a magnetic disk recording/reproducing apparatus. Moreparticularly, the invention is concerned with a magnetic head sliderassembly which is profitably suited for realizing a high densityrecording with a small gap (floating height) between a magnetic head anda magnetic disk or with a contact recording. Furthermore, the inventionis also concerned with a method of manufacturing the magnetic headslider assembly and a magnetic disk recording/ reproducing apparatusincorporating the same.

As the magnetic head slider assembly of the type mentioned above, thereis known a structure in which pads are provided on a surface of amagnetic head slider assembly. By way of example, there is disclosed inJP-A-6-36488 such a structure of the magnetic head slider assembly inwhich a pair of pads or rails (referred to as a floating surface (3) inthe above publication) are provided on a slider body for generating afloating force. This floating surface (3) is so formed as to covercontinuously a magnetic transducer and a thin film layer provided at arear end portion of the floating surface (3). On the other hand, anaerodynamic supporting type magnetic head slider assembly is disclosedin JP-A-6-52645, which assembly is provided with a pair of pads disposedat opposite sides, respectively, and a pad disposed at a rear endportion, wherein these pads are partitioned or delimited by recesses orspaces with a view to reducing the size and the weight of implementingthe magnetic head slider assembly as a whole. Of these pads, the oneprovided at the rear end portion of the magnetic head slider assembly isso formed as to present a continuous surface which covers the sliderbody, a magnetic transducer (magnetic head) and a thin film and formedof a same material as the main body of a slider. For more particulars,reference should be made to JP-A-6-52645, column 6, lines 15 to 21 and24 to 27.

Furthermore, in the case of the magnetic head slider assembly disclosedin JP-A-6-68632, such a side rail structure is adopted which includesprotrusions (51) and (52) disposed adjacent to the thin film head andelongated rail portions disposed at a leading or entrance side of themagnetic head slider assembly as viewed in the direction in which amagnetic medium is moved or rotated relative to the magnetic head sliderassembly with a view to protecting the top surface of the side railsfrom injury, wherein the elongated rail portions are isolated from theprotrusions (51) and (52) by an interposed groove. The protrusions (51)and (52) are formed of a same material as that of the slider body of themagnetic head slider assembly. For more particulars, reference should bemade to JP-A-6-68632, column 3, lines 21 to 24 and 45 to 49.

FIG. 13 is a perspective view of a conventional magnetic head sliderassembly known heretofore, FIG. 14 is a view for illustratingconceptually a floating state of the conventional magnetic head sliderassembly, and FIG. 15 is an fragmentary elongated view of FIG. 14showing a portion D indicated as encircled therein. In these figures,reference numeral 200 denotes generally the conventional magnetic headslider assembly, 210 denotes a slider body, 220 denotes a magnetictransducer or head, 211 denotes floating pads, and 223 denote cores ofthe magnetic transducers 220. Referring to the figures, in theconventional magnetic head slider assembly 200, floating pads generallydenoted by 230 are polished in order to finish smoothly the floatingsurfaces thereof. In this conjunction, it is noted that the floating pad211 provided in the slider body 210 and the floating pad 231 provided onthe magnetic transducer 220 (including a thin film thereof) differ fromeach other in respect to the hardness of the materials forming thesepads. Consequently, when the floating pads 230 undergo machining forpolishing, a height offset Hd will make appearance between the floatingpads 211 and 231 due to the difference in hardness of the materials(refer to FIG. 15). This height offset Hd will hereinafter be referredto as the process offset. The reason why such process offset makesappearance can be explained by the fact that the floating pad 231provided on the magnetic transducer 220 is formed of a soft material ascompared with the floating pad 211 of the slider body 210 and thusremoved away at a higher rate than the latter upon polishing. Such beingthe circumstances, the process offset Hd is inevitably produced in thepad of the slider body regardless of whether the pad is to serve forgeneration of the floating force or as the floating surface or theprotrusions disposed closer to the thin film head element.

By the way, it is required to reduce the floating height of the magnetichead slider assembly relative to the magnetic disk to a possible minimumin order to realize a high recording density.

In this conjunction, it is noted that when the floating height isdecreased, as mentioned above, the floating height Hs of the floatingpad provided on the slider body becomes lower than the floating heightHm of a core element 223 of the magnetic head because of the presence ofthe process offset.

For the reasons mentioned above, when the floating height is furtherdecreased, there may arise such unwanted situation that the pad of theslider body contacts with the magnetic disk before the core (element) ofthe magnetic transducer (magnetic head) is brought into contact with thesurface of the magnetic disk. More specifically, in the case of theprior art magnetic head slider assembly, the floating pad 231 of themagnetic head is provided in continuation or bonding to the pad 211 ofthe slider body 210, as described above. As a consequence of this, anend surface of the floating pad 211 of the slider body 210 comes tocontact with the magnetic disk surface 5 (FIGS. 14 and 15) in precedenceto the floating pad 231 of the magnetic head portion. Accordingly, it isimpossible to decrease the floating height more than the process offsetHd. Besides, because no physical contact can essentially be realizedbetween the magnetic transducer or head and the magnetic disk, thecontact recording is rendered impossible. Such problem equally ariseswhen the contact recording is to be performed with the magnetic headbeing contacted to the magnetic disk during rotation thereof. It willnow be understood that the process offset provides a great obstacle torealization of a high density recording.

SUMMARY OF THE INVENTION

In the light of the state of the art described above, it is an object ofthe present invention to provide a magnetic head slider assembly whichcan avoid the influence of a process offset as well as a method ofmanufacturing the same.

Another object of the present invention is to provide a magnetic diskrecording/reproducing apparatus which is capable of performing ahigh-density recording by decreasing the floating height of a magnetichead slider assembly or solving the problem presenting an obstacle to acontact recording by essentially nullifying the influence of the processoffset.

Yet another object of the present invention is to provide a magnetichead slider assembly of a novel and improved structure having only aprojecting portion which incorporates therein cores of a magnetic headformed in a thin film of a main body of the slider as well as a methodof manufacturing the magnetic head slider assembly.

In view of the above and other objects which will become more apparentas the description proceeds, the present invention is directed to amagnetic head slider assembly which includes a slider body and amagnetic head (also referred to as the magnetic transducer) formed in athin film layer provided at one side of the slider main body, wherein afloating rail or a pad adapted to contact with a surface of a magneticdisk is provided in the slider body in the form of projection(s) orprotrusion(s) extending in the direction from a bleeder surface of theslider body toward a surface of a magnetic disk for which recording/reproducing operation is to be performed by means of the magnetic headslider assembly.

According to a general aspect of the present invention, there isprovided a magnetic head slider assembly which includes a projectionincorporating or embedding therein magnetic cores of a magnetic headformed in a thin film structure and projecting in the direction facing asurface of a magnetic disk on which recording/reproducing operation isto be performed. For convenience sake of the description, theabove-mentioned projection will be referred to as the core padprojection. This core pad projection including the cores of the magnetichead is formed independently in a predetermined region of the thin filmlayer. In this conjunction, it is to be noted that with the expressionto the effect that the core pad projection is provided independently andprojects toward the magnetic disk means that the core pad projectionsdoes not extend continuously to projections or pads which may beprovided on the slider body. Accordingly, in the magnetic diskrecording/reproducing apparatus provided with the magnetic head sliderassembly according to the invention, the bleeder surface of the sliderbody which faces in opposition to a surface of the magnetic disk is sopositioned as to be retracted in the direction away from the disksurface by a distance corresponding to the height of the core padprojection.

The magnetic head slider assembly according to the present invention maybe manufactured by fabricating the magnetic head with the thin filmlayer on a substrate which is to constitute the slider body. Amongothers, the core pad projection(s) may be implemented by forming anetching mask at a predetermined location where the magnetic head is tobe formed, whereon materials are removed by a suitable process, e.g. ionetching process in the regions which are not covered with the etchingmask to thereby form the core pad projection(s).

According to the teachings of the present invention, the core padprojection of the magnetic head is positioned closer to the magneticdisk than the projections such as pad(s) formed in the slider body oralternatively in contact with the magnetic disk uponrecording/reproducing operation. Thus, even when a manufacturing offsetexists between the pad provided on the slider body and the core padprojection of the magnetic head, the magnetic head slider assembly canstably float above the magnetic disk at a predetermined angle ofincidence or stably be placed to contact with the magnetic disk.Furthermore, by spacing the pad formed on the slider body from the corepad projection of the magnetic head for a predetermined distance, thefloating height of the core pad projection of the magnetic head can bedecreased to a possible minimum which is smaller than the manufacturingoffset. In other words, the floating height of the magnetic head can bereduced shorter than that of the so-called process offset. Additionally,a contact recording in the intrinsic sense can be achieved.

Thus, according to the teachings of the present invention, obstacle torealization of a lowest floating height due to the process offsetresulting from polishing of the floating surface can substantially benullified.

The above and other objects, features and attendant advantages of thepresent invention will more easily be understood by reading thefollowing description of the preferred embodiments thereof taken, onlyby way of example, in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the course of the description which follows, reference is made to thedrawings, in which:

FIG. 1 is a perspective view showing schematically a structure of amagnetic head slider assembly according to a first embodiment of thepresent invention;

FIG. 2 is a view for illustrating conceptionally a floating mechanism ofa magnetic head slider assembly according to the first embodiment of theinvention;

FIG. 3 is a fragmentary enlarged view of a portion of the magnetic headslider assembly shown in FIG. 2 and designated as encircled in the samefigure;

FIG. 4 is a perspective view showing schematically a structure of themagnetic head slider assembly according to a second embodiment of thepresent invention;

FIG. 5 is a conceptional view for illustrating a floating mechanism ofthe second embodiment of FIG. 4;

FIG. 6 is an end view for illustrating floating states of the magnetichead slider assembly shown in FIG. 4.

FIG. 7 is a perspective view showing schematically a structure of themagnetic head slider assembly according to a third embodiment of thepresent invention;

FIG. 8 is a perspective view showing only schematically a structure ofthe magnetic head slider assembly according to a fourth embodiment ofthe present invention;

FIG. 9 is a plan view showing a structure of the magnetic head sliderassembly according to a fifth embodiment of the present invention;

FIG. 10 is a perspective view showing a structure of the magnetic headslider assembly according to a sixth embodiment of the presentinvention;

FIG. 11 is a schematic side elevational view of the sixth embodiment;

FIG. 12 is a partially enlarged view of FIG. 11 and shows a portion ofthe magnetic head slider assembly as enclosed by a circle;

FIG. 13 is a perspective view showing a structure of a prior artmagnetic head slider assembly;

FIG. 14 is a view for illustrating conceptually a floating state of theprior art magnetic head slider assembly of FIG. 13;

FIG. 15 is an fragmentary enlarged view showing a portion of the priorart magnetic head slider assembly indicated as encircled in FIG. 14;

FIG. 16 shows in a plan view an outer appearance of a magnetic diskrecording/reproducing apparatus to which a magnetic head slider assemblyaccording to the invention can profitably find application;

FIG. 17 is a perspective view showing a structure of the magnetic headslider assembly according to a seventh embodiment of the invention;

FIG. 18 is a side elevational view showing the seventh embodimenttogether with a magnetic disk;

FIG. 19 is a perspective view showing a structure of the magnetic headslider assembly according to an eighth embodiment of the presentinvention;

FIG. 20 is a perspective view showing an array of thin film magneticheads formed on a wafer through a manufacturing method according to aninth embodiment of the present invention;

FIG. 21 is a view showing a block of thin film magnetic heads resultingfrom segmentation of the array shown in FIG. 20 into elongated blocks;

FIG. 22 is a perspective view for illustrating an etching processadopted in the magnetic head slider assembly manufacturing method;

FIG. 23 is a perspective view showing a magnetic head slider assemblyincluding a magnetic head as manufactured by the method according to theninth embodiment;

FIG. 24 is a plan view of a mask employed in the etching process; and

FIG. 25 is an enlarged plan view of the mask shown in FIG. 24.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, the present invention will be described in detail in conjunctionwith what is presently considered as preferred or typical embodimentsthereof by reference to the drawings. In the following description, likereference characters designate same or like parts throughout the severalviews. Also in the following description, it is to be understood thatsuch terms as "left", "right", "upper", "lower", "rear", "front","widthwise", "transversal" and the like are words of convenience and arenot to be construed as limiting terms.

Embodiment 1

A magnetic head slider assembly according to a first embodiment of theinvention will be described by referring to FIGS. 1 and 16, in whichFIG. 1 shows the same in a perspective view and FIG. 16 shows an outerappearance of a magnetic disk recording/reproducing apparatus equippedwith the magnetic head slider assembly according to the invention. Inthis conjunction, it should be mentioned that the magnetic diskrecording/ reproducing apparatus is implemented intrinsically in asubstantially hermetically sealed structure and provided with a coverwhich is however omitted from illustration in FIG. 16. First referringto FIG. 16, a magnetic disk 162 is mounted on a spindle 163 which isrotated at a predetermined number of rotations (rpm) by means of adriving motor (not shown). A magnetic head slider assembly 161 isfixedly secured to a lever 167 which is mounted on an arm 164 which inturn is operatively coupled to an actuator 165. The arm 164 is adaptedto be driven swingably or pivotally around a spindle 166 by means of theactuator 165 so as to be indexed to desired positions on the magneticdisk 162.

A structure of a floating type magnetic head slider assembly is shown inFIG. 1. Referring to this figure, a magnetic head slider assemblydenoted generally by a reference numeral 1 is comprised of a magnetichead or magnetic transducer 20 realized in a thin film layer provided ata rear end portion of the slider body 10 as viewed in the direction inwhich the magnetic disk (162 in FIG. 16 and 5 in other figures) isrotated. The slider body is provided with a pair of floating pads 11which protrude from a slider portion of the slider body 10. The thinfilm magnetic head 20 includes a core (also referred to as the element)23 having an upper core element 23a and a lower core element 23b. A pairof pads 21 each including the magnetic head core 23 of the thin filmmagnetic head 20 protrude beyond the bleeder surface 13 of the sliderbody 10 in the direction facing the magnetic disk surface (i.e., in thedirection in which the magnetic head slider assembly is caused tofloat). These pads 21 will hereinafter be referred to as the core padprojections.

Each of the floating pads 11 is in the form of an elongated rectangularrail which is provided with a tapered portion 111 and a flat portion112. Further, each of the floating pads 11 is terminated at an end face113 without being formed in continuation to the core pad projection 21but formed independently, being distanced from the core pad projection21 by a predetermined distance in the direction toward the front edge ofthe slider body, i.e., toward the tapered portion 111. To say in anotherway, there exists a space 12 between the core pad projection 21 providedin association with the thin film magnetic head 20 and the end face 113of the floating pad 11 provided on the slider body 10. The bottom of thespace 12 is flush with the surface of the bleeder portion 13. Morespecifically, although the core pad projection 21 and the floating pads(rails) 11 are so formed as to project beyond the bottom surface of thebleeder surface 13, they are not structurally continued to each otherbecause of the interposition of the spaces 12 therebetween.

As can be seen in FIGS. 2 and 3 in which FIG. 2 is a view forillustrating conceptionally a floating mechanism of the magnetic headslider assembly according to the instant embodiment of the invention andFIG. 3 is a fragmentary enlarged view of a portion designated asencircled in FIG. 2, a height Hh between the bleeder surface 13 of theslider body 10 and the disk facing surface of the core pad projection 21which faces in opposition to the magnetic disk surface is approximatelyequal to a height Hr between the bleeder surface 13 and the flat portion112 of the floating pads 11.

Each of the magnetic heads 20 is composed of a coil 24, a connecting pad25, a substrate layer 27 and a protective film 28. In the case of themagnetic head slider assembly according to the instant embodiment of theinvention, the core pad projection 21 is realized in a rectangular formof a size of about 40 μm×20 μm and has a height of about 20 μm. Byimplementing the core pad projection 21 as a rectangular piece of thesmall size as mentioned above, the core pad projection 21 can makesubstantially no contribution to generation of a floating force. Thus,the floating characteristic of the magnetic head slider assembly isdetermined essentially by the floating characteristics of the pairedfloating pads 11. The thickness of the thin film layer 20 of themagnetic head is about 50 μm in the case of the magnetic head sliderassembly according to the instant embodiment of the invention, whichpresents no difficulty to the provision of the core pad projection 21 of40 μm×20 μm in size. Parenthetically, the slider body of the magnetichead slider assembly according to the instant embodiment of theinvention has a length of 2 mm, a width of 1.6 mm and a height of 0.4mm. It goes however without saying that the size and the form orgeometry of the slider body is never limited to those mentioned above.Of course, the size of the core pad projection 21 is never limited tothe dimensions of 40 μm×20 μm but may be implemented in any size andform so long as it has a thickness smaller than that of the thin filmmagnetic head 20 so that the former can be formed within the region ofthe thin film without departing therefrom. In this conjunction, itshould be noted that the magnetic head core 23 of the thin film magnetichead 20 is sandwiched between the substrate layer 27 and the protectivefilm 28, as can be clearly seen from FIG. 3. Thus, there arises nonecessity of modifying the shape of the core in an effort to make itconform with the geometry of the core pad projection 21.

Furthermore, by selecting the height Hr of the floating pad from thebleeder surface 13 of the slider body to the flat portion 112 of thefloating pads 11 to be equal to the height Hh of the core pad projection21, both heights being 20 μm, as in the case of the instant embodimentof the invention, it is possible to prevent the floating force frombeing generated at the bleeder surface 13. With the structure of themagnetic head slider assembly now under consideration, desired floatingcharacteristics can be realized by designing correspondingly only thepaired floating pads 11.

Referring to FIG. 2, due to the relative movement between the magnetichead slider assembly 1 and the rotating magnetic disk 5, an aerodynamicpressure is produced above the magnetic disk 5 by the floating pads 11,as a result of which the floating pads 11 are caused to float above themagnetic disk 5 with a predetermined angle of incidence because of theprovision of the tapered portions 111 at the leading side of thefloating pads 11, respectively. Additionally, the end face 113 of eachof the floating pads 11 provided in the slider body 10 is located with apredetermined distance or space from the core pad projection 21 towardthe leading edge (tapered portion) of the magnetic head slider assembly.

Furthermore, because the distance Hm from the magnetic disk surface tothe magnetic head core 23 of the magnetic head slider assembly isshorter than the distance Hs from the magnetic disk surface to the edge112a of the flat portion 112 of the floating pad 11, the floating heightHm of the magnetic head core 23 can be reduced to a possible minimum.

More specifically, even when the amount of material removed by apolishing process differs between the floating pad 11 and the core padprojection 21 due to difference in hardness thereof, which results inthat the height Hh of the core pad projection becomes smaller than theheight Hr of the floating pad 11 from the bleeder surface 13 to thefloating pad (i.e., even Hr>Hh), the magnetic head slider assembly canassume a floating state with an angle of incidence. Besides, since theend face 113 of the floating pad 11 and the core pad projection 21 aredistanced from each other, the magnetic head core 23 of the magnetichead can assume the minimum floating height Hm.

As will now be understood from the foregoing description, with thestructure of the magnetic head slider assembly according to the instantembodiment of the invention, the adverse influence of the process offsetwhich has heretofore provided an obstacle to the attempt for decreasingthe floating height of the magnetic head slider assembly can essentiallybe eliminated, making it possible to realize a high density recordingwith a decreased floating height of the magnetic head slider assembly.

Because the floating pad 11 and the core pad projection 21 are each of arectangular shape, they can be manufactured by machining. Of course,they can easily be fabricated by ion milling, etching or thin film vapordeposition process as well. The machining process is advantageous inthat it is inexpensive, while the ion milling, etching or the thin filmvapor deposition process is advantageous in that the floating pad 11 andthe core pad projection 21 can be finished arbitrarily and accurately indesired shapes, although the latter requires a lot of time when comparedwith the former.

It should further be added that the concept of the present inventionincarnated in the instant embodiment can effectively be applied torealization of data read/write operation in such state of the magnetichead slider assembly where the floating height of the magnetic head fromthe magnetic disk surface is further decreased with the floating pad 11floating without contacting the magnetic disk surface whereas a portionof the core pad projection 21 facing the magnetic disk, i.e., a portion28a of the protective film 28 is brought into continuous contact withthe surface of the magnetic disk 5. By making the core pad projection 21slide continuously on the disk surface in this manner, the gap betweenthe magnetic layer (not shown) of the magnetic disk and the magnetichead core 23 can be reduced to a possible minimum, whereby the recordingdensity can surprisingly be enhanced.

In this conjunction, the corner portion 28a of the protective film 28which is brought into contact with the magnetic disk surface may betapered or chamfered. Then, the magnetic head core 23 and the surface ofthe magnetic disk 5 can be positioned closer to each other whileobviating the damage possibly occurring upon contacting. Thus, theoperation reliability of the magnetic head can further be enhanced.

Embodiment 2

FIG. 4 is a perspective view showing schematically a magnetic headslider assembly according to a second embodiment of the presentinvention. The magnetic head slider assembly according to the instantembodiment differs from that of the first embodiment in that it has asingle core pad projection at a center of the thin film magnetic head 20as viewed in the direction widthwise of the magnetic head sliderassembly.

As in the case of the magnetic head slider assembly according to thefirst embodiment of the invention, end faces 413 of floating pads 41 areformed as displaced with a predetermined distance from a core padprojection 40 toward the leading side (tapered end) of the slider sothat a space 42 intervenes between the end faces 413 of the floatingpads and the core pad projection 40. With the structure of the magnetichead slider assembly according to the instant embodiment of theinvention, the adverse influence of the so-called process offsetproviding an obstacle to realization of the lower floating level of themagnetic head slider assembly can successfully be mitigated oreliminated.

In the magnetic head slider assembly according to the instant embodimentof the invention, the slider body 10 has an overall length of 1.0 mm, awidth of 0.8 mm and a height of 0.3 mm, wherein the floating pad (41) is0.8 mm in length (about 80% of the overall length of the slider which is1.0 mm). The height Hr from a bleeder surface 43 to a floating surfaceof each of the floating pads 41 and the height Hh of the core padprojection 40 from the surface facing the magnetic disk are each ofabout 20 μm. Of course, the geometries or dimensions of the slider arenot restricted to those mentioned above. However, it is preferred toselect the length of the floating pad as measured from the leading edgeof the slider to be about 80% of the overall length of the slider. Inother words, the end face 413 of the floating pad should preferably beso formed that the end face 413 of the floating pad is distanced awayfrom the core pad projection 40 about 20% of the overall length of theslider, the reason for which will be elucidated below.

It is now assumed that a difference of 10 nm in height makes appearancebetween the floating pad 41 and the core pad projection 40 due to apolishing process performed for securing the flatness of the floatingsurfaces. As is shown in FIG. 5, the floating pad of the magnetic headslider assembly according to the instant embodiment of the invention iscomposed of a tapered portion 411 and a flat portion 412, wherein themagnetic head slider assembly is so designed that the ratio (Hi/Hm)between the floating height Hm of the core of the magnetic head and thefloating height (Hi) of a boundary portion between the tapered portion411 and the flat portion 412 of the floating pad 41 is about "2". Ingeneral, this floating height ratio (Hi/Hm) is referred to as the gapratio, and in many cases, the slider body is so designed that this ratioassumes a value within a range of "2" to "3". In the case of themagnetic head slider assembly according to the instant embodiment of theinvention, it is assumed that the floating height Hm of the core padprojection is 50 nm. In order that the floating height Hm of the corepad portion of the magnetic head is to be smaller than the minimumfloating height Hs of the floating pad on the conditions mentionedabove, the end face 413 of the floating pad should preferably beprovided at a position which is distanced from the leading end orentrance side of the slider body about 80% of the overall length of theslider. For this reason, in the magnetic head slider assembly accordingto the instant embodiment of the invention, the length of the floatingpad is selected to be 0.8 mm. To say in another way, the end face 413 ofthe floating pad 41 is spaced from the core pad projection 21 by adistance corresponding to about 20% of the overall length of the slider.It is however obvious that the end face 413 of the floating pad may bepositioned closer to the core pad projection 40 in case the gap ratiomentioned above is designed to be greater than "2".

Furthermore, by disposing the core pad projection 40 at the center ofthe thin film magnetic head 20 as viewed in the direction widthwise ofthe magnetic head slider assembly (i.e., in the transversal direction ofthe magnetic head slider assembly), there can be achieved such advantagethat even when the magnetic head slider assembly is inclined in such amanner as indicated by a phantom line in FIG. 6 for some reason (e.g.under the effect of acceleration in the seek operation phase), thefloating height Hm of the magnetic head core will scarcely vary, as canbe seen in FIG. 6. In other words, stable floating of the magnetic headslider assembly can be realized. Thus, there can be implemented amagnetic disk recording/reproducing apparatus of high reliability,avoiding errors in the data read/write operation.

Embodiment 3

FIG. 7 is a perspective view showing schematically a structure of amagnetic head slider assembly according to a third embodiment of thepresent invention. In the case of the magnetic head slider assemblyaccording to the instant embodiment of the invention, floating pads 71and 72 of the slider body 10 are disposed with a predetermined distancefrom a core pad projection 70 which is disposed at a center of amagnetic head constituted by a thin film layer as viewed in thewidthwise direction (i.e., in the transversal direction of the magnetichead slider assembly), similarly to the case of the magnetic head sliderassembly according to the second embodiment of the invention describedpreviously. As can be seen in FIG. 7, when a plurality of pads (71; 72)are provided on the slider body, it is sufficient to space the pad (e.g.the center pad or rail 72) positioned closest to the core pad projection70 by a predetermined distance from the core pad projection 70. Owing tosuch arrangement, the low floating height of the magnetic head can berealized without undergoing adverse influence of the so-called processoffset.

More specifically, in the case of the magnetic head slider assemblyshown in FIG. 7, there are provided a pair of floating pads 71 and acenter pad 72. Each of the floating pads 71 is implemented in astructure which features the following:

(1) A neck portion or constriction 71a is provided for forming anegative pressure generating pocket on the bleeder surface.

(2) The side of the floating pad 71 located adjacent to the center lineC of the magnetic head slider assembly is so inclined that the width ofthe floating pad 71 decreases progressively as the distance from the endface 711 thereof increases (i.e., in the direction toward the front endof the slider body.

On the other hand, the center pad 72 is implemented in a structurefeaturing the following:

(1) The center pad 72 has a rear end portion whose width increasesprogressively as the distance to the core pad projection 70 decreases.

(2) The depth of the negative pressure generating pocket (bleeder depth)is decreased so that it is about 6 μm.

With the structure of the magnetic head slider assembly according to theinstant embodiment of the invention, there can be obtained advantageouseffects mentioned below. Namely, by making shallower the depth of thenegative pressure generating pocket 71b on the order of 6 μm as comparedwith the depth of the corresponding floating surface of the firstembodiment and forming the constrictions 71a in the floating pads 71 soas to form pockets 71b therebetween, it is possible to generate anegative pressure. In this conjunction, with the phrase "negativepressure", it is contemplated to mean a pressure which is lower than theatmospheric pressure and which provides a force for sucking orattracting the magnetic head slider assembly toward the magnetic disksurface.

By virtue of the structure of the magnetic head slider assemblydescribed above, there can be realized a uniform floating height of themagnetic head over the whole range from the inner periphery of themagnetic disk to the outer periphery thereof by canceling out variationsin the floating height due to difference in the radial position on themagnetic disk (i.e., in dependence on the circumferential speed and theangle of yaw). More specifically, when the circumferential speedincreases as the magnetic head slider assembly displaces radiallyinwardly, the negative pressure generating pockets 71b generate anegative pressure or vacuum for canceling out an increase of thefloating force acting on the floating pad 71. In this way, the constantfloating height can be realized over the whole area of the magnetic disk(i.e., at all the radial positions of the magnetic head sliderassembly), whereby a constant density recording with a constant linearrecording density (bits per inch) can be realized at all the radialpositions of the magnetic disk. Furthermore, by providing theconstriction 71a in each of the floating pads 71 and shaping the lattersuch that the width thereof increases progressively toward the end face711 with an inclination relative to the center line, as mentionedpreviously, a predetermined or desired floating height can be ensuredbecause the aerodynamic pressure generation efficiency can be protectedagainst degradation regardless of air flow incident obliquely to thefloating pads, which may take place during the seek operation. Besides,by providing the center pad 72, the negative pressure can be generatedstably even during the seek operation (or upon generation of the yawangle) because the sucking or attracting forces exerted by the negativepressure generating pockets and generated through cooperation of boththe lateral floating pads 71 and the center pad 72 are prevented frominterfering with each other owing to the presence of the center pad 72.Finally, it should also be mentioned that by shaping the center pad 72such that the width thereof increases toward the core pad projection 70,rigidity of an air current layer produced around the magnetic head canbe enhanced, whereby the disk tracking or follow-up performance of themagnetic head slider assembly can be improved. Owing to the advantageousfeatures mentioned above, there can be realized a stabilized floatingstate of the magnetic head slider assembly.

Embodiment 4

FIG. 8 is a perspective view showing only schematically a magnetic headslider assembly according to a fourth embodiment of the presentinvention. In the case of the magnetic head slider assembly according tothe instant embodiment of the invention, a pair of abrasion-resistivepads 81 each including no core of the magnetic head are provided at bothlateral sides of a core pad projection 80 for protecting the latter fromabrasion. These abrasion-resistive pads 81 are formed on a thin filmlayer 20 of the magnetic film similarly to the core pad projection 80 ina same height as the latter. Although it is presumed that theabrasion-resistive pads 81 are each formed in a same rectangular shapewith a same size as the core pad projection 80, it should be understoodthat the abrasion-resistive pad 81 may be formed in different shape andsize from those of the core pad projection 80 so long as the former areformed within the region of the thin film magnetic head 20. In the caseof the magnetic head slider assembly according to the instant embodimentof the invention, the minimum floating height Hm mentioned hereinbeforein conjunction with the preceding embodiments can be ensurednotwithstanding of the provision of the abrasion-resistive pads 81. Themagnetic head slider assembly according to the instant embodiment of theinvention can find profitable application to a CSS (Contact Start/Stop)type magnetic disk recording/reproducing apparatus in which the magnetichead slider assembly slides continuously on the magnetic disk uponstarting of rotation of the magnetic disk and the former is caused tofloat above the magnetic disk when the rotation speed (rpm) thereofattains a predetermined value. In that case, the abrasion-resistive pads81 share the contacting force with the core pad projection 80. Owing tothis feature, the problem of the core pad projection 80 undergoingabrasion due to the continuous contact with the magnetic disk cansuccessfully be solved. Thus, there is provided according to the instantembodiment of the invention a magnetic head slider assembly having ahigh reliability.

In the magnetic head slider assembly now under consideration, the corepad projection 80 and the abrasion-resistive pads 81 are formed in arectangular shape. However, this is never the prerequisite condition.They can be implemented in a triangular shape which may assuredust-proof effect or in a rounded shape which is excellent in respect tothe abrasion resistance.

Further, protective films may be deposited on the surfaces of the pads80, 81 facing the magnetic disk as well as on the floating surface ofthe floating pads 82 with a view to improving the abrasion resistancecharacteristics of these pads. As a protective film, there may bementioned a carbon (C) film, a silicon (Si) film, a silicon oxide (SiO₂)film or the like. The protective film may be provided in a single layeror alternatively in the form of stacked layers to thereby constitute amulti-layer film for realizing a magnetic head slider assembly capableof exhibiting excellent abrasion-resistive property and high operationreliability.

Embodiment 5

FIG. 9 is a plan view showing a structure of a magnetic head sliderassembly according to a fifth embodiment of the present invention, asviewed in the direction facing a magnetic disk. In the case of themagnetic head slider assembly according to the instant embodiment of theinvention, a center pad 92 is provided at a center position as viewed inthe direction widthwise of the thin film magnetic head 20 and closer toa core pad projection 90 than floating pads 91. In this conjunction, itis to be mentioned that by providing the center pad 92 in addition tothe pads 91 and 92 on the slider body 10 closest to the core padprojection 90 with a predetermined distance therefrom so that a space 93intervenes between the core pad projection 90 and the center pad 92, theinfluence of the so-called process offset can essentially be nullified.

The magnetic head slider assembly according to the instant embodiment ofthe invention is advantageous in the respects mentioned below.

(1) The rigidity of the air current layer produced around the magnetichead upon read/write operation can be enhanced, whereby the disktracking or follow-up capability of the magnetic head can be improved.

(2) When the magnetic head slider assembly is brought into contact withthe magnetic disk for some reason, damage which the core pad projection90 may undergo can positively be mitigated. Thus, the reliability of themagnetic head slider assembly can significantly be enhanced.

Embodiment 6

FIG. 10 is a perspective view showing a magnetic head slider assemblyaccording to a sixth embodiment of the present invention, and FIG. 11 isa schematic side elevational view of the same mounted to a thin platelever or arm 167. The magnetic head slider assembly according to theinstant embodiment of the invention is so designed as to realize acontact recording/reproducing operation.

Provided on the bleeder surface 131 of the slider body 10 which facesthe magnetic disk are sliding projections 130 each in the form of acircular column having a height Hr of about 30 μm and a diameter Ds ofabout 30 μm. By selecting the height Hr of each of the slidingprojections 130 to be at least 10 μm, the influence of air currentsgenerated in accompanying the rotation of the magnetic disk 5 can beobviated. Furthermore, in case the height Hr of each of the slidingprojections 130 is selected to be greater than 20 μm inclusive, theinfluence of the air currents can substantially be nullified. To say inanother way, it is possible to prevent generation of a floating force onthe bleeder surface 131 of the slider body 10 by the air current.Further, by selecting the diameter Ds of each of the sliding projections130 to be about 30 μm, the floating force generated by the slidingprojections 130 can substantially be nullified. In this manner, theslider body 10 can be made immune to the influence of the air currentgenerated in accompanying the rotation of the magnetic disk, which inturn means that the slider body 10 can be placed to a stable contactwith the magnetic disk surface. Furthermore, by implementing the slidingprojection 130 in the form of a circular column presenting no edge,damage such as abrasion which the magnetic head may suffer because ofcontact with the magnetic disk can be mitigated. This advantageouseffect is very important particularly for the seek operation (i.e.,operation for moving the magnetic head slider assembly radially relativeto the magnetic disk). Such effect can not be expected when the slidingprojection 130 is formed in the form of a quadrangular prism whichpresents edges.

Further formed integrally with the thin film magnetic head 20 is a corepad projection 100. Thus, the three projections 100 and 130 in total arebrought into stable contact with the surface of the magnetic disk 5.Because a pressing-down or hold-down force W is imparted to the magnetichead slider assembly 1, the core pad projection 100 can stably bemaintained in the state contacting with the magnetic disk 5 even when afloating force is generated at the sliding projections 130 and the corepad projection 100 or even when the magnetic head slider assembly tendsto move away from the magnetic disk surface for some other reason. Inthis way, the magnetic head slider assembly according to the instantembodiment of the invention can equally enjoy a high reliability withoutincurring error in the write/read (recording/reproducing) operation.

For the reasons mentioned above, the core pad projection 100 and themagnetic disk can be placed to a stable and slidable contacting stateeven when the heights Hh and Hr of the core pad projection 100 and thesliding projection 130, respectively, differ from each other due to theso-called process offset.

FIG. 12 is a partially enlarged view of FIG. 11 showing a portionenclosed by a circle. The core pad projection 100 is constituted solelyby a thin film which constitutes the thin film magnetic head 20, as inthe case of the preceding embodiments of the invention. To say inanother way, the core pad projection 100 includes no part of the sliderbody 10 but is provided independently from the latter. Morespecifically, the core pad projection 100 is comprised of a substratelayer 102, an upper core element 101a, and a lower core element 101b anda protective film 103. For fabricating the core pad projection 100,materials of the substrate layer 102 and the protective film 103 areremoved away to such extent that the magnetic core elements 101a and101b are not exposed thereby but remain sandwiched or covered betweenthe substrate layer 102 and the protective film 103, because, ifotherwise, corrosion may occur in the magnetic core 101.

Furthermore, by depositing a protective film (not shown) on the slidingprojections 130 as in the case of the core pad projection 100, thesliding performance of the magnetic head slider assembly as a whole andhence the operation reliability thereof can be enhanced. To this end, acarbon (C) film, a silicon (Si) film, a silicon oxide (SiO₂) film or thelike may be employed as the protective film.

As is apparent from the above description, in the case of the magnetichead slider assembly 1 according to the instant embodiment of theinvention, there are provided on the slider body 10 of the magnetic headslider assembly 1 a pair of sliding projections 130 which are adapted toslidably move on and along the magnetic disk surface in combination witha single core pad projection 100 formed in the thin film layer of thethin film magnetic head 20, wherein the core pad projection 100 isformed only of the thin film which constitutes the thin film magnetichead 20 so as to have a projection height which is substantially equalto that of the sliding projections 130. By virtue of this structure, themagnetic core 101 of the thin film magnetic head 20 can be placed in thestate contacting slidably and stably with the magnetic disk 5, whichcontributes advantageously to realization of an increased linearrecording density. Besides, reliability of contact write/read operationof the magnetic head slider assembly can equally be improved becausethere can positively be excluded occurrence of error due to separationbetween the magnetic core 101 and the magnetic disk 5 for some reasons.

Embodiment 7

A seventh embodiment of the present invention will be described byreference to FIGS. 17 and 18, in which FIG. 17 is a perspective viewshowing a magnetic head slider assembly according to the instantembodiment of the invention and FIG. 18 is a side elevational viewshowing the same together with a magnetic disk. In the case of themagnetic head slider assembly now of concern, only one core padprojection 100 is formed on the thin film magnetic head 20, while theother floating pads or sliding projections mounted on the slider body 10of the magnetic head slider assembly as described hereinbefore inconjunction with the preceding embodiments of the invention are allspared. The magnetic head slider assembly according to the instantembodiment of the invention is mounted on a thin-plate lever or arm 167made of a sheet material or thin plate having a triangularcross-section.

A feature of the magnetic head slider assembly under consideration canbe seen in that the number of contact points between the magnetic headslider assembly and the magnetic disk (i.e., total number of theprojections of the magnetic head core slider assembly) is decreased fromthree to one and thus the whole structure of the magnetic head sliderassembly can be implemented in a correspondingly reduced size and alight weight. This structure is advantageous in that the damage whichthe magnetic disk may possibly suffer upon siding contact with themagnetic head slider assembly can be mitigated. Besides, the tracking orfollow-up characteristic of the magnetic head slider assembly isimproved, whereby a stable contact can be ensured between the magneticdisk and the head slider assembly even when the magnetic disk issubjected to vibration. Besides, by limiting the contact point only tothe core pad projection 100, tracking of the magnetic disk can beaccomplished with high accuracy regardless of undulation (or roughness)of the magnetic disk surface.

The lever (arm) used for this kind of application is usually providedwith a pivot and a gimbals. By contrast, with the thin-plate lever of atriangular shape employed in the magnetic head slider assembly accordingto the instant embodiment of the invention, neither the pivot nor thegimbals is required. More specifically, provided on a surface of thelever 167 on which the slider is to be mounted is a printed wiring 173coated with an insulation film 181, wherein a terminal end of theprinted wiring 173 is connected to a core pad 171 of the thin filmmagnetic head by way of copper wires 172. Because the printed wiring 173is coated with the insulation film 181, the slider may be directlybonded to the lever 167 by using a suitable adhesive or a bonding agent.In that case, the magnetic head supporting means can be realized in athin structure, which leads profitably to implementation of the magnetichead/slider assembly in a thin structure as a whole.

As is apparent from the above description, there is provided accordingto the instant embodiment of the invention a magnetic head sliderassembly which ensures a high reliability and which is profitably suitedfor use in a magnetic disk recording/reproducing apparatus of a smallsize and a thin structure. Of course, the core pad projection can beformed only by the thin film constituting the thin film magnetic head20. Besides, no process offset makes appearance between the thin filmmagnetic head and the slider body because of absence of any projectionson the slider body. Thus, a stable sliding contact can be realizedbetween the magnetic disk and the magnetic head slider assembly.

Embodiment 8

FIG. 19 shows in a perspective view a magnetic head slider assemblyaccording to an eighth embodiment of the present invention. The magnetichead slider assembly according to the instant embodiment of theinvention differs from that of the sixth embodiment (FIG. 10) in that astep 190 is provided in the surface of the thin film magnetic head 20which faces a magnetic disk. Except for this difference, the structureof the magnetic head slider assembly according to the instant embodimentis substantially identical with that of the sixth embodiment (FIG. 10).The magnetic disk is rotated in the direction extending from the sliderbody 10 to the thin film magnetic head 20. Accordingly, the air currentgenerated in accompanying the rotation of the magnetic disk flowsthrough an air passage defined between the magnetic disk and a diskfacing surface 131 of the slider body 10 to be thereby directed towardthe step or offset portion 190. Because the cross-sectional area of theair flow passage is enlarged by providing the step or offset portion190, there prevails a negative pressure at this step or offset area 190.The height Hr of the step or offset portion 190 is about 5 μm. In thisconjunction, it should be mentioned that the height Hr of the offsetarea 190 should be selected smaller than ca. 18 μm because, ifotherwise, the negative pressure may possibly rise up steeply. Asmentioned previously, the phrase "negative pressure" means a pressurelower than the atmospheric pressure and exerts a force for pressing downthe magnetic head 20 toward the magnetic disk surface. Consequently,even if the magnetic disk vibrates in the course of rotation or even ifan external force is applied which tends to move the core pad projection100 away from the magnetic disk surface for some reason, the core padprojection 100 can nevertheless be maintained in the state contactingstably with the magnetic disk surface. Thus, there is provided accordingto the eighth embodiment of the invention a magnetic head sliderassembly which can enjoy high reliability without incurring no error inthe read/write operation.

At this juncture, it should be mentioned that the negative pressure Fnincreases as the offset height Hr decreases so long as the latter issmaller than about 15 μm (i.e., Hr≦ca. 15 μm). Accordingly, the heightHr should preferably be so selected that a contact surface pressure P(where P=pressing-down force W+negative pressure Fn/contacting surfacearea S) is lower than 200 kPa from the viewpoint of securing thereliability. It should further be added that in the case of the magnetichead slider assembly according to the instant embodiment of theinvention, the negative pressure becomes zero in the state where themagnetic disk is stationary even when the contact surface pressure Pduring rotation of the magnetic disk remains constant at a same valueduring rotation of the magnetic disk. Thus, the contact surface pressurecan be reduced when compared with the magnetic head slider assemblywhere the negative pressure is not made use of.

The step or offset area 190 may be formed by machining. The slidingprojection 130 and the core pad projection (gap defining projection) 100may be formed by ion milling, etching or the like process. In that case,the step or offset area 190 may be realized by taking advantage ofdifference in the milling rate (etching rate) due to difference inmaterial between the slider body 10 and the thin film magnetic head 20.In general, alumina used for forming the substrate and the protectivefilm of the thin film magnetic head 20 can be milled or etched at ahigher rate when compared with the milling rate (or etching rate) foralumina titanium carbide or zirconia used for forming the slider body10. Accordingly, when both the slider body 10 and the thin film magnetichead 20 are simultaneously milled, there results an offset (step)between the slider body 10 and the thin film magnetic head 20 due todifference in the milling rate therebetween. Thus, it will readily beunderstood that the step or offset area 190 can be formed by takingadvantage of difference in the milling rate (etching rate) between theslider body 10 and the thin film magnetic head 20.

Embodiment 9

A ninth embodiment of the present invention is directed to a method ofmanufacturing the magnetic head slider assembly described above, whichwill be described below by reference to FIGS. 20 to 25.

As shown in FIG. 20, a plurality of thin film magnetic heads 40 isformed in plural rows and columns on a ceramics substrate (wafer) 200made of, e.g. alumina titanium carbide (AlTiC) or zirconia (ZrO₂) by asputtering or the like process. The thin-film magnetic head 40 may beformed by resorting to a process similar to the conventional IC(integrated circuit) manufacturing process and is composed of a lowermagnetic film, a gap defining film, an upper magnetic film, a coil film,an inter-phase insulation film, a protective film and others.

The wafer 200 having the thin film magnetic heads 40 formed thereon issegmented into elongated blocks 210, as is shown in FIG. 21. In thisconjunction, it is to be noted that four magnetic head slider assembliesare formed in one row, wherein a wafer portion 230 of the block 210constitutes the slider body while the thin film 220 constitutes themagnetic head. Further, the cut surface of the thin film layer in whichmagnetic gap 47 is formed is destined to serve as the contact face forthe magnetic disk, while the cut surfaces of the wafer lying in a sameplane as the above-mentioned contact surface serves to constitute theprojecting contact surfaces 320 and 310, respectively (see FIG. 22). Thecontact surface 320 of the thin film magnetic head and the contactsurface 310 of the slider body 230 are polished by lapping or the likeprocess until a predetermined surface roughness as well as apredetermined gap depth is obtained with a view to smoothing the contactsurfaces mentioned above to such extent that a satisfactory contact withthe magnetic disk surface can be obtained as well as for the purpose ofadjusting the gap depth.

At this juncture, it is to be mentioned that because the thin film layer220 constituting the thin film magnetic head has a smaller hardness(i.e., softer) when compared with the ceramic wafer constituting theslider body 230, there results a so-called process offset between thecontact surface 310 of the slider body 230 and the contact surface 320of the thin film magnetic head 220 in such a manner that the contactsurface 320 of the thin film magnetic head 220 is retracted relative tothe contact surface 310 of the slider body.

For forming the sliding projections 310 and the core pad projection (orgap defining projection) 320, a mask 300 such as shown in FIG. 24 isprepared. As the mask 300, there can be used a resist mask which isconventionally employed in IC (integrated circuit) manufacturingprocesses. The mask 300 is provided with mask patterns 310a and 320acorresponding to the shapes of the sliding projections 310 and the corepad projection (or gap defining projection) 320, respectively. Morespecifically, each of the mask patterns for the sliding projections hasa circular form having a diameter of about 300 μm which is equal to thatof the slider projection 310 to be formed in the slider body 230.Similarly, the mask pattern 320a for the core pad projection 320 has arectangular form of a size of 400 μm×20 μm which is substantially sameas the core pad projection 320 to be formed in the thin filmconstituting the thin film magnetic head. The mask for the core padprojection is so prepared as to cover the core or gap, the upper andlower magnetic films, the substrate and a portion of the protective filmand provided only for the contact surface of the magnetic head.

As can be seen in FIG. 24, the mask 320a for the core pad projection isprovided on the contact surface 220 of the thin film magnetic head andpositioned on a center line 410 between the paired masks 310a for thesliding pad projections 310 with a predetermined distance Lg from thecontact surface 230 of the slider body. The mask pattern 320a isprovided in a region including the substrate film 44, a lower magneticfilm 42a, the gap film 47, the upper magnetic film 42b and theprotective film so as to encircle the lower magnetic film 42a, the gapfilm 47 and the upper magnetic film 42b.

Subsequently, an etching process is carried out by using the mask 300mentioned above to thereby remove away the materials of those regionswhich are not covered with the mask. In the manufacturing methodaccording to the instant embodiment of the present invention, theetching is carried out by using argon (Ar) ions. It is however apparentthat other ions may be employed to this end. After removal of thematerials from the regions which are not covered with the mask, thoseportion covered with the masks remain as they are, to thereby formprojection.

After the etching process, the masks are delaminated, and then theproduct is cut along a boundary line 400, whereby one magnetic headslider assembly shown in FIG. 23 can be obtained.

Although the etching process is adopted as a method of forming theslider projections and the core pad projection, it goes without sayingthat a machining process may equally be employed in place of the etchingprocess. Namely, materials exposed through the mask patterns may beremoved by using a grinder or the like machining tool. Although themachining process is advantageous in that the manufacturing cost is low,it is not suited for finishing a product of complicated and precisegeometries such as a curvilinear surface. By contrast, the etchingprocess is suited to a high-precision finishing of a product of acomplicated shape. However, the etching rate is relatively low, taking alot of time for the processing. By way of example, the etching rate liesgenerally within a range of several microns to several ten microns perhour. Thus, the etching process is not suited for removing a largeamount of material. Such being the circumstances, the optimal processingmethod should be selected by taking into account the shapes of thesliding pad projections and the core pad projection. Of course, thefloating pad mentioned hereinbefore may be formed through the processdescribed above.

As will now be appreciated from the foregoing description, according tothe teachings of the invention, the so-called process offset effect canvirtually be eliminated between the slider body and the magnetic headcore portion. By virtue of this feature, a low floating height of themagnetic head can be realized. Alternatively, the magnetic head and themagnetic disk can be brought into stable contact with each, whichcontributes to realization of a high recording density without incurringerror in the write/read operation of the magnetic head.

Many modifications and variations of the present invention are possiblein the light of the above techniques. It is therefore to be understoodthat the invention may be practiced otherwise than as specificallydescribed without departing from the spirit and scope of the invention.

We claim:
 1. A magnetic head slider assembly comprising:a slider body; athin film layer disposed at one end of said slider body; a magnetic headconstituted by said thin film layer; and a core pad projection providedon said thin film layer, which said magnetic head is incorporated in,and wherein said core pad projection constitutes no part of said sliderbody and is so formed as to project towards a magnetic disk beyond anadjacent disk facing surface of said slider body immediately in front ofsaid core pad projection; a sliding pad provided at a region of saidslider body ahead of said core pad projection for preventing generationof a floating force by making use of a relative movement between saidslider body and said magnetic disk, said sliding pad being so formed asto project beyond the disk facing surface of said region of said sliderbody; and wherein said core pad projection and said sliding pad areseparated from each other a predetermined distance longitudinally ofsaid slider body by a recess interposed therebetween whereby the coreDad projection and the magnetic disk are placed to a stable and slidablecontacting state even though said back end of said sliding Dad projectsfrom said disk facing surface of said slider body by a distance which islonger than a distance by which said back end of said core padprojection projects from said disk facing surface of said slider body.2. A magnetic head slider assembly according to claim 1 wherein a pairof spaced sliding pads are provided at a region of said slider bodyahead of said core pad projection and said core pad projection isdisposed substantially at a center line between said pair of slidingpads.
 3. A magnetic head slider assembly comprising:a slider body; athin film layer disposed at one end of said slider body; a magnetic headconstituted by said thin film layer; and a core pad projection providedon said thin film layer, which said magnetic head is incorporated in,and wherein said core pad projection constitutes no part of said sliderbody and is so formed as to project towards a magnetic disk beyond anadjacent disk facing surface of said slider body immediately in front ofsaid core pad projection; a sliding pad provided at a region of saidslider body ahead of said core pad projection for preventing generationof a floating force by making use of a relative movement between saidslider body and said magnetic disk, said sliding pad being so formed asto project beyond the disk facing surface of said region of said sliderbody, and having a height projecting beyond the disk facing surface ofsaid slider body which is greater than a height said core pad projectionprojects beyond the disk facing surface of said slider body; and whereinsaid core pad projection and said sliding pad are separated from eachother a predetermined distance longitudinally of said slider body by arecess interposed therebetween whereby the core pad projection and themagnetic disk are placed to a stable and slidable contacting state eventhough said back end of said sliding pad projects from said disk facingsurface of said slider body by a distance which is longer than adistance by which said back end of said core Dad projection projectsfrom said disk facing surface of said slider body.
 4. A magnetic headslider assembly according to claim 3 wherein a pair of spaced slidingpads are provided at a region of said slider body ahead of said core padprojection and said core pad projection is disposed substantially at acenter line between said pair of sliding pads.